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The article informs that opera singers and train opera singers are at high level in music colleges. It mentions that the history of the opera offers is only in the Repertoire and ensemble theaters in Central Europe can be vividly experienced. It also mentions that departments for singing and music theater measure themselves against this claim Generation of young singers for the international opera business.

The paper presents a simple technique for correctly and fastly tuning the slip gain in Indirect Field Oriented Control drives. To this aim no other transducers than the tachogenerator, usually included in such drives, are needed, as the tuning operation is performed by processing the effects of a suitable test signal injected in the system. The proposed approach can be used either for on-line retuning of working drives, either for the initial tuning of new installed drives. Simulation and experimental tests show that the procedure is effective and does not Interfere with normal operations of the drive.

A full procedure; is presented in this paper to provide a straightforward tool useful for parameter determination of Permanent Magnet Synchronous Motors. Classical tests, that are well established to measure the parameters of synchronous machines with conventional field excitation, are reviewed to confirm or not their applicability. A novel test performed during particular transient conditions allows us to evaluate one of the concerned motor time constants. The motor behaviour is simulated by means of a simulation language (ACSL) on a digital computer and several runs in different transient conditions are performed. Comparison of the simulated and experimental vaweforms of speeds and currents shows good agreement and confirms the validity of the proposed procedure.